Signal-controlled positioning apparatus



CRQ'SS REFERENCE w. H. sAYLoR SIGNAL-CONTROLLED POSITIONING APPARATUSDec. 30, 1969 3,486,388

Filed June 27, 1968 2 Sheets-Sheet 1 I vnvram Patented Dec. 30 lgfigjILS. I'll. 74-96 It) @Iaims AIESTRAC'I OF THE DISCLOSURE A mechanism (asfor use in a display apparatus) is disclosed along with solenoidactuators, for selectively positioning a frame or array that may defineany of a variety of images or the like. The frame ismoved along a some-What-arcuate path by a pivotal support structure that may be variouslyactuated, as by a solenoid drive unit. Another pivot structure actuatesthe frame along an intersecting somewhat-arcuate path so that thecombination of movements' may accomplish selective two-dimensionalpositioning. In one embodiment the pivot structure includes twosomewhat-similar parallel links to the frame which preserve aparallelogram configuration as the frame is variously positionedenabling improved space utilization. The system is disclosed toadditionally include: counter balancing weights for the pivotalstructures to accomplish gravitational independence, a locking structureincluding a pairof intersecting arcuate racks for engagement by a singledetent, and a limiting toggle structure for gaging the extent ofdisplacement.

FIELD OF THE INVENTION The present invention relates to positioningapparatus as controlled by electrical signals and is a continuation-impart of U5. pending patent application, Ser. No. 458,973 filed May 26,1965, now Patent No. 3,448,444.

BACKGROUND AND SUMMARY OF THE INVENTION The need frequently arises tovariously physically position a member in accordance with controlsignals. For example, a signal-controlled display device may include amechanism to variously position a plane array of symbols to accomplishthe selective individual display of one particular symbol. Such devicesmay incorporate optical apparatus and a ource of illumination to afforda projected light display. In prior-art forms of such display devices,it has been proposed to move the array (or the frame sup porting thearray) in sliding contact with supporting members. However, in systemsof this type, frictional forces inherent in sliding elements, makeaccurate control exceedingly difficult, with the result that the arrayis continually subject to misalignment with the optical system.

A desirable characteristic for a mechanism to position In general, thepresent invention resides in a positioning mechanism which utilizes apair of arcuate-motion drive structures. The system may be adapted to awide variety of applications as for example, systems to displayphotographic slides mounted in a frame as a single-plane array, systemsfor symbolic displays and so on. The system here of enables a compactpattern of the individual displays by introducing a parallel mode ofoperation. More specifi=- an array of symbols, as in a displayapparatus, is independence from gravitational forces. Various systems ofthe prior art which utilize slides, ratchets and other similarmechanisms have sometimes presented a substantial load to be moved whichis difficult if not impossible to balance for gravitationalindependence.

In the operation of a signal-controlled positioning ap paratus, it isalso sometimes desirable to lock the frame cally, with regard tostructure, in accordance with one embodiment hereof, the frame to bepositioned is mechanically coupled by dual links from pivot points tothe pivotal structure. As a result of such an arrangement, a stable,reliable, accurate and parallel, pivotal positioning struc ture isafforded which may incorporate balance weights, a locking mechanism thatutilizes a single detent and an effective alignment mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, which constitute apart of this specification, there are set forth exemplary embodimentsdemon strating various objectives and features hereof, specifically:

FIGURE 1 is a perspective and diagrammatic view of a systemincorporating a structure in accordance with the present invention;

FIGURE 1a is a diagram illustrating the basic opera tion of a structureas may be embodied in the system of FIGURE 1;

FIGURE 2 is a diagrammatic and plan view of a some- What-simplifiedstructure incorporating the principles of the present invention;

FIGURE 3 is a diagrammatic and top plan view of a mechanism constructedin accordance with the present invention;

FIGURE 4 is a sectional view taken along line 4-4l of FIGURE 3; and

FIGURE 5 is a sectional view taken along line 5-5 of FIGURE 3.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS As required, detailedillustrative embodiments of the invention are disclosed herein. In thatregard, it is to be understood that these embodiments exemplify theinvention although various different forms thereof may be con-=structed. In any event, the embodiments set forth herein are presentedas a basis for the claims defining the scope of the invention and topresent a basis for an understanding thereof.

Referring initially to FIGURE 1, there is shown a somewhat-diagrammaticperspective view of a system incorporating apparatus of the presentinvention. Specifically, a housing It contains a frame (not shown) whichin turn holds a light mask defining an array of symbols (not shown)which may be employed to symbolically modulate, define, and/or color abeam of light that is indicated by a line I2. In one application, thehousing III may receive the light mask through a slot 24, which maskcarries an array of photographic projection slides that are selectivelydisplayed on a screen 14 via the beam represented by the line 12.

The housing 10 receives illumination from a light source 16 through anaperture 18 which is generally aligned with a lens holder 2th. Thestructure contains a lens system as generally well known in the priorart for light image projection. The mechanism within the housing It)aligns a selected symbol or portion of an array with the aperture 18 tothereby light-modulate and display a selected image. Such positioningmay be accomplished by a solenoid unit or other motive means (not shown)contained within the housing It), that is selectively energized throughan electrical cable 22. Thus, electrical signals supplied through thecable 22 command the display of a particular image on the screen 14, byselectively positioning a frame within the housing to ac- :omplish therequisite alignment with the aperture 18.

The basic pattern of motion within the housing 10 is illustrated inFIGURE la. A mask 23 defines several patterns, e.g. light projections,of varying opacity to form light images. The mask 23 is carried on agenerally vertical post 24 which is pivotally connected to horizontallinks 25 and 27. The link 25 is in turn pivotally connected to a pivotmember 29 while the link 27 is anchored at a fixed pivot point 31. Thepivotal movement of the link 27 (as by a solenoid drive unit) displacesthe mask 23 along a somewhat vertical arcuate path, while such movementof the pivot member 29 accomplishes somewhat horizontal displacement.Thus, the two motion paths in combination are capable of providingselective two-dimensional positioning of the mask 23.

Although the structure depicted in FIGURE 1a is effective, there arecertain problems in its use. For example, as the mask moves in anarcuate pattern (providing several attendant advantages) the individualprojection images (normally rectangular) must be placed in a somewhatfan-shaped configuration which does not afford a compact array.Furthermore, it is desirable to include structure for precisely placingthe mask 23 in each selected position, compensating for mechanicalslippage, wear and so on.

One form of more sophisticated structure is shown in FIGURE 2 and willnow be considered in detail. A frame 26 (shown in phantom) supports anopaque mask 28 defining an array of symbols 29, which mask is to bevariously positioned with respect to an optical system 30. The frame 26is connected through a generally-indicated pivotal mechanism 32 tosolenoid drive units 34 and 36. Specifically, the drive unit 34 controlsthe displacement of the frame 26 along an arcuate path which issubstantially horizontal, while the drive unit 36 positions the frame 26along a substantially-vertical arcuate path.

Considering the mechanism 32 in greater detail, a horizontal arm or link38 is connected from a dual pivot point 40 (on the right vertical leg 42of the frame 26) to a floating pivotal connection 44. Thus, the link 38is coupled to a pivotally-mounted actuation arm 46. The arm 46 includes:a major vertical extension 48 from a fixed pivot 50 to the pivotalconnection 44; and a shorter horizontal extension 52 from the fixedpivot 50 providing a lever arm for the solenoid drive unit 34) and acounter-balancing weight arm 54.

The extension 52 is coupled to the solenoid drive unit through amechanical linkage, represented by dashed lines 56, in accordance withwell known techniques. In this regard, the solenoid drive unit 34 mayoperate with binary-code displacement, driving the extension 52rotationally about the pivot 50 in binary-code increments. Thus, as theextension 52 is raised or lowered by discrete motions (in asubstantially arcuate pattern) such motion is translated through thelink 38 to traverse the frame 26 along a substantially-horizontalarcuate path.

The major vertical displacement of the frame 26 is accomplished througha pair of parallel'vertical links 58 and 66 which are of similar length.The link 68 is connected from the pivot point 40 to a floating pivotalconnection 62 of the member 64, the horizontal extension 66 of whichalso includes a pivotal connection 68 to the link 58.

A vertical downward extension 70 of the member 64 terminates at afloating pivotal connection 72 that is coupled to an actuating arm 74,mounted at a fixed pivotal reference point 76. A short horizontalextension 78 of the member 74 is mechanically coupled to the solenoiddrive unit 36 (indicated by dashed lines 80) whereby to rotatablydisplace the arm 74 in accordance with energizaticn of the solenoiddrive unit 36, as in binary significance.

The weight of the frame 26 along with certain of the structure issomewhat counter-balanced by the weight 54 along with the weight 82afiixed to the extension 78 of the arm 74. The facility to accomplishsuch counter-balancing is a significant feature of the. presentstructure as it enables dynamic response that is identical for allpositions of the system. Anothei feature hereof is illustrated by anarcuate extension 86 from the vertical link 60. The extension 86provides a su'pport or guide for the swinging generally-horizontal link38 as it moves in relation to the link 60. Such a support or guideaffords a considerable advantage in a pivotal system incorporating theprinciples of the present invention.

Another important feature of the structure of FIGURE 2 is illustrated bythe parallel links 58 and 60. These members hold the frame 26 in aparallelogram configuration with the extension 66 thereby enabling amuch more compact arrangement or pattern of the individual images. As aconsequence, a significantly increased area within the frame 26 may beusefully employed. Somewhat similarly, for the vertical, an extension 87from the member 64 receives a pivotal arm 89 at a floating pivot point91. The arm 89 is fixed at a pivot point 93 to provide a parallelism forthe frame 26 in cooperation with the actuating arm 74 (of similaroperational length).

Considering the actual operation of the system of FIG- URE 2, tovariously position the frame 26 in accordance with arcuate displacementof the extension 52 and 78 of the drive units 34 and 36, respectively,it is to be noted that the parallel links 58 and 60 consistentlymaintain the frame 26 in referenced alignment. That is, as the solenoiddrive unit 34 actuates the arm 46 to move the link 38 laterally, therebydisplacing the frame 26 horizontally, the two links 58 and 60 swing infixed relationship to the arm 64, preserving the motion of the frame 26in an established vertical orientation pattern. Somewhat similarly,asthe solenoid drive unit 36 actuates the arm 74, to raise and lower theframe 26, through the arm 64 and the. links 58 and 60, the pivot link 89is cooperatively instrumental in maintaining the frame 26 orientedthroughout the arcuate vertical-motion path.

By differently energizing the solenoid drive units 34 and 36 as wellknown in the art, various symbols 29 that are defined in the array 28may be aligned with the optical system 30 to thereby project a lightimage of such a symbol. Thus, signals applied to the solenoid driveunits may position the frame 26 to accomplish a desired positionalrelationship and in turn present a desired display as depicted in FIGURE1.

A still more-sophisticated embodiment of the present invention isillustrated in the remaining FIGURES 3, 4

and 5, which will now be considered in detail. In these figures theframe (generally coinciding to the frame 26) is shaded in order tobetter distinguish it from the connecting arms and linkages.Fundamentally, the frame 100 is moved in a manner substantially similarto that previously described with reference to FIGURE 2. Specifically,the frame 100 is supportedly carried by a pair of pivotal connections.102 and 104 and driven by a pair of solenoid units 106 and 108.

The pivotal connection 102 on the frame 100 receives an angular link 110which is connected through a floating pivot connection 112 to an arm 114that is carried on a fixed pivot mount 116 supported on a base. plate117. The

arm 114 is also connected through a pivotal connection 118 to a drivecontrol member 126 which is mechanically connected (as indicated by adashed line 122) to be actuated by the solenoid unit 106.

The drive control member 120 is connected for drive at three pivotpoints which are spaced apart to incrementally move the arm 114 withdisplacements of binary sign ficance, e.g. 1, 2, 4, etc. That is, thedrive control member 120 gages the displacement of the frame 100 topredetermined. vertical distances. Thus, although the motive force isapplied in an arcuate pattern, the control memher .120 limits thedisplacement of the frame. 100 to horizontal projections of the arcuatepattern.

iwhich is driven between limit stops 1% in the base plate 117 throughend connections 127 and 129, by the solenoid drive unit 1'06. i

Recapitulating, with regard to the mechanism generally, the solenoidunit 106 acts on the drive member 5120 to variously pivot the arm 114about the fixed pivot 116. As a result, the pivotal junction 112 (upperright) swings along an arcuate path which is a somewhat horizontalmotion pattern that is directly applied through the link 110 to thepivotal connection 102 on the frame 100. Thus, various discretedisplacements accomplished by the solenoid unit 106 (which may bearcuate) result in various displacements of the frame 100 along asubstantially-horizontal, arcuate motion path metered to lineardisplacement.

The substantially-vertical displacement of the frame 100 is accomplishedby the solenoid unit 108, acting through links 136 and 138 which aresimilar in length and parallel, both being connected from the frame 100to an arm 140 at spaced-apart pivotal connections 142 and 1441. The arm140 is referenced to a fixed pivot amount 146 on the base plate 117,through a generally horizontal link 148 (top of drawing) and a pivotalconnection 150. The arm 140 is also referenced to a fixed pivot mount154 (also on the base plate 117) through a link 1156 pivotally coupledat the connection 158 (lower left). The toggle drive and guide member121 is connected through a pivot connection 162 to the arm 156 andcarries drive ends 166 and 16%. The end 168 is coupled to the solenoiddrive 108 (mechanical coupling 169) while the end 16 6 is pivotallycoupled to a toggle-like member 171 which operates between limit stops174). In the same manner, the end 168 operates between limit stops 172which are affixed in the base plate 117.

The vertical motion pattern is accomplished when the solenoid unit 108variously displaces the drive member 121 to pivot the link 156 about thepivot mount 154, thereby moving the pivotal connections 142 and 1 14,raising or lowering them along generally-arcuate vertical paths ln thismanner a desired vertical position of the frame 100 is accomplished. Bycombining such generally-vertical displacement and the similargenerally-horizontal displacement (as considered above) two-dimensionalposition selectivity is provided for the frame 100, whereby variousparallel sections, Within the frame 109 may be selectively aligned withan optical system 1% for display.

in the system, the solenoid units 106 and 108 actually provide overdrive to the control members 120 and 121 which limit the actualdisplacements to measured horizontal and vertical linear projections. Asboth members operate in the same manner, consider the lower,less-obstructed member 121. As indicated above, drive is applied fromthe solenoid unit 1118 to the ends of the toggle-like member 171 and theend 168. The left (outward) end of the toggle-like member 171 has avertical displacement indicative of a value of one. Ina related manner,the other end of the toggle-like member 171 is displaceable between thelimit stops 1711 to accomplish a displacement of two. The movement atthe end 168 of the control member 121 has an applied significance offour. Thus, by selectively placing each of these junctions in raised orlowered positions, eight difierent displacement positions are available.Thus, the positions are accurately defined, in addition to being in aparallel configuration which permits dense packing.

Regarding other structure of the system of FIGURE 3, the floatingpivotal connections, as the connection 15b,

may comprise simply a pin 1112 (FIGURE 5) locked into the connectingmembers, e.g. link 14% and link 1156 by a snap ring 184. The pivotalsupports which are fixed to the base plate 117 are afforded bearingsupport. Specifically, for example, the pivot support 154 (FIGURE 4)includes an elongate pin 186 extending through the linki15ti, bearingelements 188 and terminating in a snap ring 190. Thus, the link 156 ispivotally anchored to the base plate 117.

In the operation of the system of FIGURE B, various predeterminedpositions for the frame 101} are accomplished selectively energizing thesolenoid units 106 and 108. A selected position can be maintained, afterthe solenoid units are de-energized. The structure for accomplishingthis operation involves a pair of overlapping, curved racks 202 and 204which are arcuate about pivots 154 and 116, respectively, each carryingteeth which are engaged by a solenoid-detent structure 206. The rack 202defining teeth 202a is carried on the link 156 and is coupled through aspring 208 to the base plate 117. The rack 204,- including teeth 204a,is carried on the arm 114 which is coupled through a spring 210 to thebase plate 117.

In operation, the solenoid-controlled structure 2% is energizedresulting in the withdrawal of a detent 212, after which the solenoidunits 106 and 108 may freely act to position the frame in the desiredphysical relationship to the base 98 and the optical system as describedabove. Subsequently, the solenoid structure 206 is die-energizedallowing the detent 212 to be released into mutujal engagement with theracks 202 and 204, thereby locking the two pivotal systems in thepositions in which they are placed. As a result, a selected position ismaintained until the solenoid 206 is again energized. Thus, the systemmay incorporate a simple memory structure. I

The system hereof may be economically produced in a low-maintenance formthat is capable of accomplishing desired positional relationships inaccordance with electrical control signals or various other motivemeans. The system may be embodied in small miniature units or sizabledisplay systems. Of course, many different forms are possible and inthat regard the scope hereof is indicated by the claims hereof.

What is claimed is:

1. A mechanism for selectively positioning an array along first andsecond intersecting paths in a single plane comprising:

a first pivot means including a first arm affixed thereto,

for movement in a first defined arc in said plane; means for couplingsaid first arm to said array, whereby to traverse said array primarilyalong a first path;

a second pivot means including a second arm affixed thereto for movementin a second defined arc in said plane which second defined arcintersects said first defined arc;

linkage means including at least one connection on said array, and atleast one linkage means coupled to each of said first and second pivotmeans whereby to traverse said array variously along said first andsecond intersecting paths to thereby selectively position said array intwo dimensions.

2. A mechanism according to claim 1 wherein said linkage means includesat least two links of substantially equal lengths and connected inparallel configuration to said array.

3. A mechanism according to claim 1 further including first and secondarcuate index means, said first index means coupled respectively to saidfirst and second pivot means, and still further including detent meansfor mutually engaging said index means.

4. A mechanism according to claim 1 wherein said linkage means furtherincludes a pivot arm extending in one dimension; and at least two pivotson said pivot arm, coupled to said two links at spaced-apart locationsthereon.

5. A mechanism according to claim 4, wherein said two links are ofsubstantially equal length.

6. A mechanism according to claim 11 further including at least onesupport extension integral with an element of said linkage means, forsupporting at least one other of said means.

7. A mechanism according to claim 1 further including at least onecounter-balance means coupled to one of said pivot means whereby toafford somewhat of a balance.

8. A mechanism according to claim 7 wherein said two links are ofsubstantially equal length and further in eluding first and secondarcuate index means, said first index means coupled respectively to saidfirst and second pivot means, and still further including detent meansfor mutually engaging said index means.

9. A mechanism according to claim 8 further including at least onesupport extension integral with an 10 element of said linkage means, forsupporting at least one other of said means.

10. A mechanism according to claim 1 further including a displacementlimiting apparatus including a plurality of pivotally-mountedinterconnected toggle means and means for limiting the displacement ofsaid toggle means.

References Cited UNITED STATES PATENTS FRED C. MATTERN, 111., PrimaryExaminer W. S. RATLIFF, 111., Assistant Examiner US. Cl. X.R. 340347;350--269

